Color imaging devices produce combinations of different colorants to form color images on print media such as paper or film. Many imaging devices make use of combinations of cyan, magenta, yellow, and black (CMYK) to reproduce the gamut of a color image. Ideally, different imaging devices produce identical color output. Differences in hardware and print media, however, can result in substantial variation.
To provide a better colorimetric match, many color management systems execute color transformations. A color transformation manipulates input color data to drive the output of a destination device toward the output of a source device. A color transformation can be applied, for example, to match the output of a color proofing system to that of a printing press.
Common color transformation functions are either one-dimensional (1-D) or multi-dimensional (M-D). A one-dimensional transformation relies on single-input, single-output functions that are applied on a channel-independent basis. In other words, color data for each colorant channel, e.g., C, M, Y, and K, are manipulated independently of other channels to produce a desired visual output.
A multi-dimensional transformation function, in contrast, may specify a mixture of the output colorants for a given input, taking into account interactions between the different colorant channels. For digital color proofing, multi-dimensional functions generally are more effective in achieving a color match between the images produced by the source and destination devices. In this example, the source refers to the device to be matched, e.g., a printing press. The destination refers to the device for which the transformation will be applied, e.g., a digital color proofer.